Summary & Overview

CPT 29879: Arthroscopic Knee Cartilage Repair and Microfracture

CPT code 29879 covers arthroscopic knee procedures focused on repair of articular cartilage using techniques such as debridement, surface reshaping, drilling, excision, and microfracture to stimulate bone marrow and promote healing. This code matters nationally because cartilage procedures are common drivers of orthopedic surgical utilization, influence post-operative rehabilitation pathways, and have implications for payer coverage, prior authorization, and bundled payment design.

Key payers examined include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise clinical description, the expected sites of service, common billing and documentation considerations, and an overview of typical payer engagement. The publication outlines typical clinical context for use of the code and summarizes reimbursement and policy patterns relevant to national stakeholders.

The report provides benchmarks for utilization and reimbursement (where available), summarizes policy updates affecting arthroscopic cartilage procedures, and situates CPT code 29879 within clinical care pathways for knee joint preservation and symptomatic relief. Data not available in the input is identified explicitly, and readers are directed to payer-specific guidelines for coverage criteria and billing practices.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicare29879CPTarthroscopyknee surgerycartilage repairmicrofractureorthopedicsoutpatient surgery

Billing Code Overview

CPT code 29879 describes an arthroscopic procedure on the knee joint in which the provider examines the interior of the joint with an arthroscope and repairs damaged articular cartilage. Techniques described include reshaping or grinding the cartilage surface, drilling or excising cartilage, and puncturing underlying bone to create small fractures that encourage new growth. The procedure is intended to relieve pain and improve joint mobility.

Service type: Arthroscopic knee cartilage repair, debridement and microfracture techniques
Typical site of service: Ambulatory surgical center or hospital outpatient department

Clinical & Coding Specifications

Clinical Context

A 52-year-old active patient presents with progressive medial knee pain, mechanical catching, and limited range of motion after a degenerative meniscal tear confirmed by MRI. Nonoperative care including activity modification, physical therapy, anti-inflammatory medication, and intra-articular corticosteroid injection provided temporary relief but symptoms persisted. The orthopedic surgeon schedules an arthroscopic procedure to evaluate and address intra-articular pathology.

The procedure is performed in an ambulatory surgery center or hospital operating room under regional or general anesthesia. The surgeon introduces an arthroscope into the knee joint to inspect the articular surfaces, menisci, and synovium. Treatment consists of debridement and arthroscopic chondroplasty — smoothing and reshaping damaged articular cartilage, performing microfracture or drilling into subchondral bone when indicated to stimulate fibrocartilage repair, and excising unstable cartilage flaps. Postoperative care includes recovery monitoring, pain control, weight‑bearing as tolerated or protected as indicated, and a progressive physical therapy program to restore motion and strength.

Typical documentation elements include preoperative diagnosis, informed consent, anesthesia type, operative findings, specific arthroscopic maneuvers (chondroplasty, debridement, microfracture/drilling), laterality, any concurrent procedures, estimated blood loss, complications (if any), and postoperative plan.

Coding Specifications

Modifier	Description	When to Use
`59`	Distinct procedural service	When a separate, distinct procedure is performed on the same day that is not normally bundled with the arthroscopic chondroplasty and meets modifier `59` criteria.
`51`	Multiple procedures	When more than one procedure is reported at the same operative session in addition to the primary arthroscopic chondroplasty.
`52`	Reduced services	When the procedure is partially reduced or not completed as originally planned.
`53`	Discontinued procedure	When the procedure is started but discontinued due to extenuating circumstances or patient condition.
`78`	Unplanned return to OR for related procedure during postoperative period	When the patient returns to the operating room for a related procedure during the global period.
`79`	Unrelated procedure by same physician during postoperative period	When an unrelated procedure is performed by the same provider during the global period.
`RT`	Right side	To indicate the procedure was performed on the right knee.
`LT`	Left side	To indicate the procedure was performed on the left knee.
`22`	Increased procedural services	When work required to perform the procedure is substantially greater than typically required. Documentation must support increased effort.
`26`	Professional component	When billing only the professional component separate from the technical component (rare for arthroscopy but applicable if separate technical services exist).
`50`	Bilateral procedure	When identical procedures are performed bilaterally during the same operative session.
`63`	Procedure performed on infants less than 4 years of age	Use when procedure is performed on qualifying age group.
`62`	Two surgeons	When two surgeons work together as primary surgeons performing distinct operative responsibilities.
`58`	Staged or related procedure during postoperative period	For planned staged procedures or a procedure related to the original during the global period when appropriate.

Taxonomy Code	Specialty	Notes
207K00000X	Orthopaedic Surgery	Primary specialty performing knee arthroscopy and chondroplasty.
208800000X	Physician Assistant	Common assistant provider conducting perioperative care and assisting in arthroscopy.
207L00000X	Sports Medicine (Orthopedics)	Subspecialists frequently perform arthroscopic cartilage procedures for athletes and active adults.
164W00000X	Physical Therapist	Manages postoperative rehabilitation and documented functional milestones.
207R00000X	Hand Surgery (Orthopaedic Subspecialty)	Data not applicable; included as placeholder.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`M17.11`	Unilateral primary osteoarthritis, right knee	Degenerative articular cartilage leading to pain and disability; common indication for chondroplasty and microfracture.
`M17.12`	Unilateral primary osteoarthritis, left knee	As above for the left knee.
`M23.2X1`	Derangement of medial meniscus due to old tear or injury, right knee	Meniscal tears often coexist with articular cartilage damage addressed at arthroscopy.
`M23.2X2`	Derangement of medial meniscus due to old tear or injury, left knee	As above for left knee.
`S83.241A`	Complex tear of medial meniscus, current, right knee, initial encounter	Acute meniscal injury with cartilage involvement may prompt arthroscopic repair or debridement with chondroplasty.
`M94.261`	Chondromalacia patellae, right knee	Cartilage softening and breakdown of the patella contributing to anterior knee pain; treated with arthroscopic chondroplasty when conservative care fails.
`M94.262`	Chondromalacia patellae, left knee	As above for the left knee.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`29870`	Arthroscopy, knee, diagnostic, with or without synovial biopsy	Diagnostic arthroscopy may be performed before or in combination to evaluate intra-articular pathology; often billed when diagnostic arthroscopy is primary.
`29881`	Arthroscopy, knee, with meniscectomy (medial OR lateral, including any meniscal shaving)	Performed when a meniscal tear is present and requires partial meniscectomy in addition to chondroplasty.
`29875`	Arthroscopy, knee, synovectomy, limited	Performed when inflamed synovium requires debridement during the same arthroscopic session.
`29999`	Unlisted procedure, arthroscopy	Used for arthroscopic procedures or adjuncts not described by specific CPT codes; requires supporting documentation.
`29879`	Arthroscopy, knee, chondroplasty (including debridement/microfracture)	Primary procedure described; included here for completeness and linkage to associated procedures.